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Genetic variation affects de novo translocation frequency.

ABSTRACT: Translocation is one of the most frequently occurring human chromosomal aberrations. The constitutional t(11;22)(q23;q11), which is the only known recurrent non-Robertsonian translocation, represents a good model for studying translocations in humans. Here we demonstrate polymorphisms of the palindromic sequence at the t(11;22) breakpoint that affect the frequency of de novo translocations in sperm from normal males. A typical allele consists of a perfect palindrome, producing ~10-5 de novo t(11;22) translocations. Alleles with an asymmetric center do not form the t(11;22). Our data show the importance of genome sequence on chromosomal rearrangements, a class of human mutation that is thought to be random.

SUBMITTER: Kato T

PROVIDER: S-EPMC2818512 | biostudies-literature |

REPOSITORIES: biostudies-literature

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DNA secondary structure is influenced by genetic variation and alters susceptibility to de novo translocation.

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